25 years ago - Ray Terrill is born the son of Lanford Terrill. He is brought up by foster parents, believing his is light-allergic.
8 years ago - 17-year-old Ray's foster father is killed in a car accident. He discovers his father is Lanford Terrill, and that he has heightened versions of his father's powers. He becomes the Ray, confronting S.H.A.D.E. His father goes underground.
3 years ago - 22-year-old Ray sacrifices himself to help save the rest of the Justice League from the White Martian attack.
Ray Terrill debuted in 1992, and definitely looked it. It was a deliberate, focused attempt to create something very of the time, and it worked. The new modern character would maintain a place as a recurring background character even after his initial series was over.
The exact placement of Ray Terrill in the timeline is a little unclear specifically because he was introduced as a new character in the early nineties and appeared in the Justice League, but then made another appearance several years later alongside Young Justice. While his first appearance (and that fact that he became and actual Justice League member) made him seem to be in his late teens, almost a decade later he was being depicted alongside the other members of Young Justice, all of whom were depicted as between 14 and 16. This could easily be because of the youthful, kinetic art of Humbeto Ramos, but whatever the reason, it calls into question his age and just what part of the DC universe he falls into.
Ultimately, we decided to focus on his relationship with his father, and his subsequent time with the Justice League. It allows him to have a truly heroic moment when he sacrifices himself to save the rest of the Justice League, capping his story with a dramatic flourish.